1. Field of the Invention
The present invention relates to a display panel, and more particularly, to a display panel in which shapes of address electrodes may be improved to prevent cross-talk.
2. Discussion of the Related Art
Plasma display panels (PDP) are generally referred to as flat display devices. In a typical PDP, a discharge gas is injected between two substrates on which a plurality of electrodes are formed, the two substrates are sealed, and a discharge voltage is applied to the substrates. When the discharge gas radiates between two electrodes, a proper pulse voltage is applied to the two electrodes to perform addressing in a place where the two electrodes cross. The discharge gas is excited to produce ultraviolet light, which in turn excites a fluorescent layer thereby producing visible images.
Such a PDP may be a direct current (DC) PDP or an alternating current (AC) PDP, depending upon the drive voltage that is applied to a discharge cell. Depending upon discharge cell electrode structure, PDPs may also be classified as a face discharge type and a surface discharge type.
With a DC PDP, all electrodes are exposed to a discharge space and electric charges directly move between facing electrodes. With an AC PDP, at least one electrode is covered with a dielectric layer so that instead of directly moving electric charges between facing electrodes, ions and electrons generated due to a discharge produce a wall voltage by sticking to the dielectric layer's surface, and the discharge is sustained by a sustaining voltage.
In a face discharge type PDP, an address electrode faces a scan electrode in each unit pixel, and addressing and sustaining discharges occur between them. In a surface discharge type PDP, an address electrode and a sustaining electrode are prepared in each unit pixel to cause addressing and sustaining discharges.
FIG. 1 shows a unit cell of a conventional PDP 10. Referring to FIG. 1, the conventional PDP 10 includes a front substrate 11 and a rear substrate 15 facing the front substrate 11. A pair of sustaining electrodes 12 are formed on the front substrate 11 to predetermined width and height, a front dielectric layer 13 is formed on the sustaining electrodes 12 using a printing method, and a protection layer 14 is formed on the front dielectric layer 13.
An address electrode 16 is formed on the rear substrate 15 to predetermined width and height, and a rear dielectric layer 27 is formed on the address electrode 16. Barrier ribs 18 are disposed on the rear dielectric layer 17 to prevent cross-talk from occurring between adjacent discharge cells. Red, green, and blue fluorescent layers 19 are formed on an upper surface of the rear dielectric layer 17 and on inner walls of the barrier ribs 18.
An inert gas is injected into a space between the front and rear substrates 11 and 15 to form a discharge area 100.
The operation of the conventional PDP 10 having the above-described structure will now be described in brief.
When a drive voltage is applied to the sustaining electrodes 12, a surface discharge occurs from the front dielectric layer 13 and the discharge area 100 on the protection layer 14. The discharge produces ultraviolet rays that excite the red, green, and blue fluorescent layers 19 to achieve a color display.
In other words, the drive voltage accelerates the discharge cell space charges, which collide with a pressurized penning gas comprised of an inert gas such as neon (Ne) mixed with helium (He), xenon (Xe), or other like gases.
As a result, the inert gas produces ultraviolet rays of 147 nanometers, which then collide with the red, green, and blue fluorescent layers 19 to produce visible rays.
FIG. 2 shows an electrode structure according to the prior art. Referring to FIG. 2, X and Y electrodes 21 and 22 are alternately arranged in a stripe shape on the front substrate 11 of FIG. 1. Address electrodes 23 are arranged in a stripe shape, on the rear substrate 15 of FIG. 1, orthogonally to the X and Y electrodes 21 and 22. Barrier ribs 24 disposed between the address electrodes 23 define discharge spaces.
However, since these conventional electrodes have wide widths, they cause high power consumption when representing low gray scale or actual moving pictures. Thus, prominent electrodes have been suggested to solve these problems.
FIG. 3 shows a layout of prominent electrodes according to the prior art. Referring to FIG. 3, X and Y electrodes 31 and 32 are alternately arranged in a stripe shape on the front substrate 11. Address electrodes 33 are arranged in a stripe shape, on the rear substrate 15 of FIG. 3, orthogonally to the X and Y electrodes 31 and 32. Barrier ribs 34 are formed between the address electrodes 33. Prominent electrodes 35 are formed at portions of the address electrodes 33 that cross with the Y electrodes 32 so as to provide a suitable electrode area for stable address discharging. The prominent electrodes 35 protrude from sidewalls of the address electrodes 33 to a predetermined width.
The electrode structure of FIG. 3 is an asymmetric structure in which a width W3 of an area B coated with a blue fluorescent layer is wider than widths W1 and W2 of areas R and G coated with red arid green fluorescent layers. Thus, a sufficient gap may exist between the address electrode 33G and the address electrode 33B. As a result, the address electrodes 33G and 33B may be prevented from interfering with electric charge characteristics of the green and blue fluorescent layers.
However, a sufficient gap may not exist between the address electrode 33R and the address electrode 33G, which may affect an electric field between them. In this case, external factors may easily affect the wall charges of the address electrodes 33, which may result in undesired cross-talk.
FIG. 4 shows a second layout of prominent electrodes according to the prior art. Referring to FIG. 4, a width W6 of an area B coated with a blue fluorescent layer has the same size as widths W4 and W5 of areas R and G coated with red and green fluorescent layers. Prominent electrodes 45 are formed at portions of address electrodes 43 that cross with Y electrodes 42. Similar to FIG. 2 and FIG. 3, the X and Y electrodes 41 and 42 are alternately arranged in a stripe shape.
In this case, a sufficient gap may not exist between an address electrode 43G and an address electrode 43B. Thus, although a bather rib 44 is disposed between the address electrodes 43G and 43B, they may affect an electric field distribution according to electric charge characteristics of the green and blue fluorescent layers.